Please allow me to verify a little background on this issue:1. If you re-deploy FileMaker Server (Admin Console > FileMaker Overview page > Edit Server Deployment), does FileMaker find the machine's web server without any issue? If so, how long does the web publishing engine run before you experience the crashing i.e. can you make a php call to FileMaker x times before getting this error?2. Can you access FileMaker via Instant Web Publishing? (If this is FIleMaker Server Advanced)3. Is it possible to change the default port from 80 to 591, FileMaker's alternative default port? This may affect your other websites, however.4. Are you using SSL?

It may be beneficial to have you send in a zipped FileMaker Server > Logs folder. I will send you a private message with information about where you can send this file. To view this message, click on the Inbox link in the upper right corner of this forum.